1. Field of the Invention
The present invention relates generally to electrical circuits, and more particularly to voltage regulators.
2. Description of the Background Art
A voltage regulator generates a regulated output voltage from an input voltage. A buck regulator is a voltage regulator that generates an output voltage smaller than the input voltage, while a boost regulator is a voltage regulator that generates an output voltage larger than the input voltage. A buck-boost regulator is a voltage regulator that generates an output voltage smaller, equal, or larger than the input voltage. A voltage regulator may employ pulse width modulation (PWM) to vary the ON time of a drive transistor to generate a regulated output voltage.
The PWM DC (direct current) operating point of a voltage regulator, which affects the over current headroom and noise sensitivity of the regulator, dictates the duty cycle of the drive transistor for a given input voltage and output voltage. While a circuit designer may optimize the PWM DC operating point to a sweet spot, e.g., particular input voltage, output voltage, and duty cycle, such optimization typically involves reconfiguration of the voltage regulator to meet the needs of particular applications. This poses a problem for voltage regulator device manufacturers who may need to offer the same voltage regulator to different customers with varying applications.